Click for next page ( 19


The National Academies | 500 Fifth St. N.W. | Washington, D.C. 20001
Copyright © National Academy of Sciences. All rights reserved.
Terms of Use and Privacy Statement



Below are the first 10 and last 10 pages of uncorrected machine-read text (when available) of this chapter, followed by the top 30 algorithmically extracted key phrases from the chapter as a whole.
Intended to provide our own search engines and external engines with highly rich, chapter-representative searchable text on the opening pages of each chapter. Because it is UNCORRECTED material, please consider the following text as a useful but insufficient proxy for the authoritative book pages.

Do not use for reproduction, copying, pasting, or reading; exclusively for search engines.

OCR for page 18
10 Exhibit 4. The INPUTS worksheet of the DIETT spreadsheet application. without requiring the user to study the structure of the entire ceived). The default values reflect generalized approxima- spreadsheet. Adjusting the default values listed on the INPUTS tions developed by the analysts. The default values should be worksheet should be sufficient for the generation of the top- changed to better reflect state averages, and, for the selected tier TCPs. Changing the values creates list scenarios (prioritized top-tier TCPs, further (regional or local) refinements may be lists). Summary instructions for making the default value appropriate. adjustments are provided on the screen. After the default values are reset, click on the "Calculate"but- The default values are grouped into those measuring trans- ton, at the bottom of the screen to view results. This will calcu- portation impact and those measuring direct economic impact late all the fields and take the user to the OUTPUTS worksheet (Exhibit 4). (see Exhibit 5). Transportation impact measures the direct cost of the dis- ruption to commercial (freight) shipping by measuring the net 2.2.2 The OUTPUTS Worksheet cost of using less direct routes--detours. For trucks and rail a The OUTPUTS worksheet contains columns A through CG, $/ton/mile cost is used to adjust for the increased distance, but only shows columns A through F and CC through CG. and volume categories (low, medium, and high) are used to Columns G through CB are hidden. The viewable portion of estimate the time-delay factor. For barges, costs of delay and the OUTPUTS worksheet provides the disruption impact esti- cargo losses are the principal cost drivers. The default values provided are generalized, national-level estimates. These should mate. The results are displayed as follows: be changed to better reflect state averages, and, for the selected Column CC shows transportation-related impacts, top-tier TCPs, further (regional or local) refinements may be Column CD shows direct economic impacts, and appropriate. Column CE shows total impacts. Direct economic impact measures the direct economic cost associated with increases in business costs caused by the intro- These columns are can be sorted. Column CE is the recom- duction of a detour into freight shipments. The tool considers mended sorting method. After sorting, some of the rows may the costs associated with the increased time shipments spend contain "corrupted" data. These data require adjustment in the en route as well as costs associated with altered risk (real or per- CHOKE POINTS worksheet.